Safety blow-off valve



sept. 15 .1924. 1,508.635

' R. C. WOODHAM I SAFETY BLOW OFF. VALVE Filed Sent; 16, 1922 2Siesta-Sheet l wuentoz Sept. 16, 1924, 1,508,635

7 R. C. WOODHAM SAFETY snow OFF vulva Filed sent} 16, 1922. 2Sheets-Sheet 2 Patented Sept. 16, 1924.

stares earner means tries.

sarnrr Brow-ore vanvn.

Application filed September 16, 1922. SerialNo. 588,727.

To alZ whom it may concern Be it known that I, RAYBON C. VVOODHAM,

a citizen of the United States, residing at Montgomery, in the county ofMontgomery and State of Alabama, have invented certain new and usefulImprovements in a Safety Blow-Off Valve, of which the following'is aspecification.

My invention relates to improvements in safety blowoif valves.

An object of my invention is to provide a safety blowoff valve wherein,if the operating mechanism therefor becomes broken, the steam ispositively prohibited from escaping, thereby preventing burning orotherwise injuring persons who might be standing nearby.

A still further object of my invention is to provide a safety blowoifvalve wherein if the engine had a side rod get loose and break, theoperating mechanism for my safety blowoff valve, there would be no lossof water and steam and the engineer could make the necessary repairs andproceed without blockin g the tratlic which would be the case if the oldform of valve was used.

A still further object of my invention is to provide a safety blowoffvalve that will not allow the steam to escape when the engine is wreckedthereby insuring the safety of the lives of the engineer and othersagainst burning by the steam.

' A; still further object of my invention is to provide a safety blowoffvalve which may be easily opened when desired and that is strong,durable, simple and inexpensive in construction and that is well adaptedto the use for which it is designed.

Other objects and advantages of the invention will. become apparentduring the course of the following description.

In the drawings, wherein like numerals:

are employed to designate like parts throughout the same,

Figure 1 is a longitudinal section through the valve structure,

Figure 2 is a section taken on line 22 in F 1, looking in the directionof the arrow,

Figure 3 is a section taken on line of Fig. 1, looking in the directionof the arrow,

Figure 4 is a detail view of the valve stem guide yoke used inconjunction with my in vention,

Figure 5 is a side elevation of'apparatus embodying my invention, and

Figure 6 is anend elevation of the cage member. p

In the drawings, wherein for the purpose of illustrationis shown thepreferred em: bodiment of my invention, the numeral 10 designates theboiler wall which is provided with a threaded opening adapted to receivethe body portion 11 which is of hollow cylindrical formation providedadjacent one end with the threads 3, while the other end thereof isprovided with a hollow semispherical extension 13 having internalthreads adjacent its end for receiving the casing member 1a which isprovided with internal threads 15 intermediate its ends for receivingthevvalveseat 16, which is prefer ably provided with hexagonal faces 17 asis clearly shown in Fig. 2 of the drawing, so that an ordinary wrenchmay be'used to remove the valve seat when it is necessary. A head 18 isthreadedly mounted on the end of the casing member 1% being providedwith a centrally located aperture for receiving the bushing 1.9 throughwhich the rod 20 slides to project interiorly of the casing member 1 1.

A valve 21 provided with a downwardly extending-pin 22 is movable withinthe portion of the casing member'lt adjacentthe 1 extension 13 and isadapted to engage with the valve seat 16; This valve 21 is mounted onthe valve rod 20 and held securely in place by'means of jam nuts 23. Thedownwardly extending pin 22 of the valve 21 is adapted to be receivedbetween the spaced upwardly extending flanges 24: formed in the casingmember 14. It will thus be seen that by reason of the pin 22 slidablymounted between the upstanding flanges 2 1, the valve 21 willpositively'be guarded against lateral movement and swaying from itsoriginal seat by whirling sprays of water and steam blowing against itfrom the boiler when in use. A valve stem yoke guide 25 is mountedwithin the body member 13 by means of the screw threads 26. The valvestem rod 20 extends through the valve 21,;the valve stem yoke guide 25and projects through the body 11. One end of a coil spring 2'! bearsagainst A cage sleeve 28 has one end provided with threads 29 forengaging the threaded reduced end of the body 11 and its other endclosed by a nut shaped wall 30 so that a wrench may engage therewith,the end of the body portion 11 being formed with a valve seat 31engageable by a ball check valve 32 confined within said cage sleeve 28.This cage sleeve and its end wall is formed with a plurality ofapertures 33 so that the water and steam may be passed therethroughwhereas foreign matter will be prevented from passing therethrough suchas filings or other light foreign substances which are usually found ina boiler. When the check valve 32 is seated upon the valve seat 31 it isin engagement with the terminal end of the stem 20.

An operating mechanism is provided for the valve stem rod20'comprising afulcrumed support 34 upon which is mounted a lever 35 pivotedintermediate its ends and curved downwardly so as to pivo-tally engagethe rod 20 as at 36. A suitable handle member 3'7 is engaged with theother end of the lever 35 whereby? it may be fulcru'med for pushinginwardly upon the rod 20 thereby unseating the valve 21 which also movesthe stem so as to unseat the check valve 32 and allow the boiler steamto escape. The immeral 38 designates a suitable Water out- It will thusbe seen that I have described a safety blow off valve, that willpositively not allow steam or water to escape, except when the handle 37is operated. In other words the steam pressure within the boiler will atall. times hold the check valve 32 in engagement with its seat 31 untilthe rod 20 which is operated by the lever 35,

.unseats the ball 32 thereby allowing the steam and water to escapethrough the body 11, the casing 14k and then through the pipe 38. Itwill further be noted that ii the steam pressure gets so low that thepressure will not be sufficient to hold the ball 32 in its seat 31, thevalve 21 will prevent the steam from escaping and as the pressure withinthe boiler increases, the ball 32 will be caused to seat in the seat 31.It is to he noted that'the valve stem guide yoke is so constructed thatthe steam and water passing through the body 11 is unhindered but 1tdoes form an adequate support for the valve stem 20. My invention is adecided improvement over the other forms of blow off valves now in use,in that it positively prevents the escape of steam if the operatspiritof my invention or the scope of the subjoined claims.

Having thus described myinvention, I claim 1. A device oi. the classdescribed includ ing a valve body portion having a pair of valveseatstherein, a disk valve engageable with one of the valve seats, a ballcheck valve engageable with the other valve seat, a cage member forreceiving the ball valve when in open position disposed adjacent itsvalve seat, a stem projecting through the first mentioned valveengageable with the ball valve to move the ball valve from its seat whenthe disk valve is moved from its seat, and means forholdingthe diskvalvenormally in engagement with its seat, and means for moving the diskvalve from its seat when desired.

2. In combination, a body portion having a valve seat adjacent one end,and an enlarged extension at its other end a valve casing memberthreadedly mounted in said enlarged extension and provided with a valveseat intermediate its ends, a disk valve engageable with said lattervalve seat, means for moving the disk valve from its seat, a stemprojecting through the disk valve and through said body portion, a valvestem guide threadedly mounted in said body portion in its enlargedextension, said stem projecting through said guide, a spring disposedabout the stem between the guide and the disk valve, a cage on the endof said body portion adjacent its valve seat, a check valve mounted inthe cage and adapted to be moved from its seat by the stem when the diskvalve is moved from its seat in the manner and for the purposespecified.

In testimony whereof I affix my signaturein presence 01 two witnesses.

RAYBON C. WOODHAM.

- lVitnesses: WV. B. Honors,

CLAXTON C. DE LANEY.

